SPS SPS FM Pure 2026 November — Question 3 9 marks

Exam BoardSPS
ModuleSPS FM Pure (SPS FM Pure)
Year2026
SessionNovember
Marks9
TopicPolar coordinates
TypeShow polar curve has Cartesian form
DifficultyChallenging +1.2 This is a standard Further Maths polar coordinates question requiring conversion from Cartesian form, finding a maximum using calculus, and computing an area integral. While it involves multiple steps and FM content, the techniques are routine: substituting x=r cos θ, y=r sin θ, differentiating to find maxima, and applying the standard polar area formula. The algebraic manipulation is straightforward and the question structure is typical of textbook exercises.
Spec4.09a Polar coordinates: convert to/from cartesian4.09b Sketch polar curves: r = f(theta)4.09c Area enclosed: by polar curve

The figure below shows the curve with cartesian equation \((x^2 + y^2)^2 = xy\). \includegraphics{figure_3}
  1. Show that the polar equation of the curve is \(r^2 = a \sin b\theta\), where \(a\) and \(b\) are positive constants to be determined. [3]
  2. Determine the exact maximum value of \(r\). [2]
  3. Determine the area enclosed by one of the loops. [4]

The figure below shows the curve with cartesian equation $(x^2 + y^2)^2 = xy$.

\includegraphics{figure_3}

\begin{enumerate}[label=(\alph*)]
\item Show that the polar equation of the curve is $r^2 = a \sin b\theta$, where $a$ and $b$ are positive constants to be determined. [3]
\item Determine the exact maximum value of $r$. [2]
\item Determine the area enclosed by one of the loops. [4]
\end{enumerate}

\hfill \mbox{\textit{SPS SPS FM Pure 2026 Q3 [9]}}